The present invention relates to a mirror actuator assembly which is used in vehicles for remote adjustment of a reflective mirror element in a rearview mirror assembly, especially an exterior rearview mirror assembly. More particularly, the present invention relates to the housing for the mirror actuator assembly and to an improved electrical distribution system within the housing.
Mirror actuator assemblies used to adjust the orientation of a mirror element supported in a mirror assembly typically include at least one or more motors and appropriate gearing. The actuator motor drives the gearing, which in turn drives a positioning member. The positioning member extends from the gearing and through the mirror actuator housing to engage the back of the mirror element backing plate. Conventional mirror backing plates include a ball mount or semi-spherical structure that engages a pivot structure on the actuator housing so that the mirror element and mirror backing plate can freely pivot as a unit about the pivot structure. As the positioning member is extended and withdrawn in and out of the actuator housing, the mirror element and mirror backing plate rotate about an axis extending through the pivot structure.
The actuator motor is powered by a 12-volt supply from the vehicle or vehicle ignition system through an electrical distribution system in the actuator housing, which electrically couples the motor to the vehicle power supply, and is generally powered in the 9-volt to 16-volt, 12-volt nominal range. Conventional electrical distribution systems comprise a plurality of wires that extend from the motor's positive (+) terminal to the power supply and from the motor's negative (-) terminal to ground. Typically, the wires' proximate ends are soldered or crimped to motor connectors which electrically couple the wires to the motor's terminals. The wires, extending from the motor and actuator housing, are then soldered or crimped at their distal ends to external connectors for coupling to the vehicle power supply.
Several problems have developed with the conventional electrical distribution systems in mirror actuators. Because these electrical distribution systems include loose wires that are fixed only at two points--at the motor terminals and at the point where the wires leave the housing for connection to the vehicle power supply--they are subject to vibration, which may result from the vehicle engine, from travel over rough roads, or from wind pressure on the mirror assembly. Vibration can cause the wires to disconnect and to contact adjacent wires or conductive surfaces creating a short or a non-functional mirror. Furthermore, the manufacture of such an actuator with a conventional electrical distribution system is labor intensive. The wires are cut to length. The insulation on the wires must be removed at their distal ends. Then the proximate and distal ends of the wires are soldered or crimped or otherwise permanently attached to motor connectors and external connectors. The motor connectors are then soldered or otherwise permanently coupled to the motor's terminals. The wires are then positioned in the housing and directed out of the housing. Those portions of the wires which extend exteriorly of the housing are then, typically, bundled together in a harness for protection.
In another conventional actuator assembly, the electrical distribution system comprises three metal plates which extend from inside the housing to outside the housing. One plate extends to the respective ground terminals of two motors housed in the actuator assembly housing, and the other two plates extend to the respective power terminals of the two motors. The plates include bent ends for connecting to the motors and extend from the housing body into a plug connection port provided on the housing wall exterior for connection to a vehicle power supply. The plates are installed by snapping them into a pre-molded housing base and are held in place by abutments formed on the molded housing base. The disadvantage of this particular electrical distribution system is that it requires tight fabrication tolerances on the plates and on the housing and the housing abutments, which hold the plates in place. Moreover, this assembly process is also highly labor intensive and, as the ends of the plates extend through exit holes provided in the side wall of the base, a sealant is still required to prevent moisture and debris from entering the actuator housing through the exit holes. Lastly, the assembly process may subject the plates to damage. When snapped into the place, the plates are easily bent and, consequently, may no longer provide good contact with the motors.